Disclosed is an amino acid composition which can accelerate the burning of a fat by marathon or the like, improve endurance, reduce fatigue, reduce obesity and improve anti-stress ability. Specifically disclosed is an amino acid composition comprising 3.0-10.0 parts by mass of aspartic acid, 2.5-9.0 parts by mass of threonine, 2.0-9.5 parts by mass of serine, 12.0-40.0 parts by mass of glutamic acid, 7.0-20.0 parts by mass of proline, 0.5-4.5 parts by mass of glycine, 1.0-4.5 parts by mass of alanine, 3.0-12.0 parts by mass of valine, 0.1-0.8 part by mass of cystine, 1.5-5.0 parts by mass of methionine, 2.0-8.0 parts by mass of isoleucine, 5.0-15.0 parts by mass of leucine, 3.0-10.0 parts by mass of tyrosine, 3.0-10.0 parts by mass of phenylalanine, 4.0-15.0 parts by mass of lysine, 0.8-4.0 parts by mass of tryptophan, 1.5-5.0 parts by mass of histidine, and 2.0-6.0 parts by mass of arginine relative to 100 parts by mass of the total amount of the amino acids.
